What Is a Programming Language?

So what does it mean to call something a "programming language"? To understand this term, you need look no further than the language you use to speak and write. At its most fundamental level, human language is composed of two things—words and rules:

The words are groupings of letters that have a common meaning among all the people who speak the same language. For example, the word "book" denotes a particular type of object and the word "read" denotes a particular type of action.

The rules are the ways in which words can be combined so as to create coherent and understandable concepts. If you want to be understood by other speakers of the language, then you have only a limited number of ways to throw two or more words together. "I read a book" is an instantly comprehensible sentence, but "book a I read" is gibberish.